Abstract
Purpose: :
This retrospective case series aims at sharing our experience with the Toric Implantable Collamer Lens in twelve eyes with myopic astigmatism secondary to pellucid marginal degeneration (PMD).
Methods: :
All consecutive cases with PMD that were implanted with a TICL by HVG from January 1, 2005 to December 31, 2008 were retrospectively reviewed for postoperative outcomes. Preoperative Evaluation: Preoperative ophthalmic examination included best corrected distance visual acuity (BCVA); manifest refraction by autorefraction (Canon, RK-F1); keratometry, anterior chamber depth, corneal topography by OPD Scan II (ARK 10000, Nidek) and Orbscan® IIz (Bausch and Lomb); and axial length by partial coherence interferometry (IOLMaster version 5, Carl Zeiss, Meditec). Diagnosis of PMD was based on this data, analysis of corneal topography indices by the Corneal Navigator feature of the OPD Scan II (ARK 10000, Nidek), and clinical judgment. Postoperative Evaluation: All eyes were examined postoperatively at 1 day, 1 week, 1 month, 3 month, and 6 months. Outcome measures were recorded at the last postoperative visit and included uncorrected distance visual acuity (UCVA), BCVA, manifest refraction, and corneal topography using the same devices as preoperatively.Statistical Analysis: The mean and standard error of the mean (SEM) were calculated for the following variables: age, preoperative and postoperative BCVA, preoperative and postoperative spherical equivalent, and postoperative UCVA. Histograms detailing refractive outcome data were prepared using Microsoft® Excel 2002 (Microsoft® Corporation).
Results: :
The sample consisted of twelve eyes in six patients. The mean age was 41.2 years ± 3.3 (SEM). The mean BCVA was 0.07 ± 0.06 logMAR (20/23) preoperatively and -0.02 ± 0.03 logMAR (20/19) postoperatively. The mean postoperative UCVA was +0.14 ± 0.04 logMAR (20/28). The mean preoperative spherical equivalent (SE) was -5.98 ± 0.90 diopters (D), and at 6 months follow-up, the mean postoperative SE was -0.10 ± 0.19 D. Ten eyes (83 percent) had improvement in their BCVA after surgery. One patient reported severe glare and halos in one eye postoperatively requiring subsequent removal and replacement of the TICL due to a hyperopic refractive surprise.
Conclusions: :
Implantation of the TICL appears to be a safe and effective surgical procedure for the correction of myopic astigmatism in eyes with PMD.
Keywords: refractive surgery: phakic IOL • astigmatism • keratoconus